(a) Technical Field
The present invention relates to a method for controlling an air control valve in a diesel hybrid vehicle, and more particularly, to a method capable of reducing the noise and vibration associated with a throttle valve in the diesel hybrid vehicle by controlling the throttle valve to be closed and then to be opened again for a predetermined time when a diesel engine is stopped and a vehicle speed is less than a predetermined speed.
(b) Description of the Related Art
Generally, a diesel engine has the advantages of realizing high fuel efficiency and torque compared to a gasoline engine. Also, the diesel engine sucks air and compresses it at high compression ratio and then causes auto-ignition by using a high compression temperature more than 500° C. in the combustion process of fuel, whereas the gasoline engine mixes air and fuel and then ignites it via an electric spark. However, conventional diesel engines have experienced problems including generation of great vibrations and loud noise.
The diesel engine vehicles according to the related art embody an air control valve (ACV) operation logic by detecting whether an ignition is off in order to reduce a travelling vibration.
However, since the situation has been frequently generated in the diesel hybrid vehicles that a motor is operated and the diesel engine is stopped while travelling at low speed, there have been the problems that the vibration/noise is frequently generated due to the air control valve during operation of diesel hybrid vehicles.